Question: Before the previous stop there were 38 people riding on a train. 10 people ended up getting off at the stop. How many people are riding the train now?
Explanation: The number riding the train now is the difference between the number who were riding and the number who got off at the previous stop. The difference is $38 - 10$ people on the train. $38 - 10 = 28$ people are on the train.